Can you tell me how can i restrict the uploaded file to make it read only? I mean, for example, I uploaded a .pdf file on the server and i want that when the user access the file, it can open but they CANNOT save it in their local machine. Is that possible?

I want not only with the .pdf file. I have different file on my server. .xls, .doc, .ppt etc. I just want that, if the user access the file, they can open it for the review purposes by i don't want them to save the file on their local machine.

this is my sample codes:
<?php

echo "<a href='folder/sample.doc'>"."Sample 1"."</a>";
?>

now i want that when the user access the "sample.doc", they can view it but they are not able to save it.